Dermatology practice gaps: Missed diagnoses

KAUAI, HAWAII – Up to 130,000 patients hospitalized for treatment of lower extremity cellulitis annually in the United States turn out to have been misdiagnosed – and therein lies an opportunity for dermatologists to make a difference, according to Erik J. Stratman, MD, chairman of the department of dermatology at the Marshfield (Wisc.) Clinic.

As a section editor for UptoDate, he monitors the medical literature to identify practice gaps in dermatology, which he defines as things he and, he suspects, many other dermatologists are “either doing or not doing in practice that we shouldn’t or should be doing,” he explained at the Hawaii Dermatology Seminar provided by Global Academy for Medical Education/Skin Disease Education Foundation.

Bruce Jancin/Frontline Medical News

Dr. Erik J. Stratman

At the Hawaii meeting, he zeroed in on two such practice gaps pertaining to missed diagnoses.

Lower extremity cellulitis

A 2017 American Academy of Dermatology report on the national burden of skin disease contained eye-popping figures on the heavy toll of cellulitis. Cellulitis is the most common form of skin and soft tissue infection (SSTI). To put that into perspective, the annual incidence of SSTIs is 10-fold greater than that of pneumonia. Indeed, SSTIs account for 10% of all infectious disease–related hospitalizations across the country. There are 2.3 million emergency department visits per year for cellulitis, 14%-17% of which result in hospitalization (J Am Acad Dermatol. 2017 May;76[5]:958-972.e2).

Dr. Stratman, who is on the board of directors of the American Board of Dermatology, was favorably impressed with the work of a multicenter group of investigators who scrutinized 259 consecutive patients admitted with a diagnosis of lower extremity cellulitis through the emergency department at Massachusetts General Hospital in Boston. Seventy-nine of them (30.5%), were found to be misdiagnosed. Fifty-two of the 79 misdiagnosed patients had been admitted primarily for treatment of their supposed cellulitis: 44 of these 52, or 85%, didn’t require hospitalization, and 48 of the 52, or 92%, received unnecessary antibiotics.

Extrapolating from this experience, with application of cost data provided by the U.S. Agency for Healthcare Research and Quality, the investigators estimated that misdiagnosis of cellulitis results in 50,000 to 130,000 unnecessary hospitalizations annually. These hospitalizations for what the investigators termed “pseudocellulitis,” the majority of which is stasis dermatitis, resulted in inpatient costs estimated at up to $515 million per year. The unnecessary hospitalizations also led to an estimated 9,000 nosocomial infections, up to 5,000 Clostridium difficile infections, and a projected two to six cases of anaphylaxis resulting from exposure to the unnecessary antibiotics (JAMA Dermatol. 2017;153[2]:141-6).

Dr. Stratman said that the large Massachusetts General Hospital study mirrors his own experience when called upon to do a hospital consultation, as well as that of other dermatologists he has spoken with: “The number-one reason we get consulted is for stuff that is wrongfully admitted, mainly cellulitis.”

The investigators then went on to develop a simple prediction model for lower extremity cellulitis based upon their data. It’s called the ALT-70 score, an acronym for Asymmetric, Leukocytosis, Tachycardia, and Age greater than 70. A patient gets 3 points if one leg is affected, zero if both are. Age 70 or more is worth 2 points. A heart rate of 90 beats per minute or higher gets 1 point, as does a WBC of at least 10,000 per uL. A score of 0-2 spells at least an 83% likelihood that the patient has pseudocellulitis, while a score of 5 or points indicates at least an 82% likelihood of true cellulitis (J Am Acad Dermatol. 2017 Apr;76[4]:618-625.e2).

“If you don’t reach a score of 3, you’d better think a little bit harder before you hang that bag of vancomycin,” Dr. Stratman observed.

He ascribed the huge problem of misdiagnosed lower extremity cellulitis to several causes: emergency medicine physicians, hospitalists, and primary care physicians receive minimal dermatology training. In addition, there are no reliable diagnostic studies for the infection, and dermatologists are seldom consulted on patients with red legs, either because there are no dermatologists in a particular community or they don’t want to be consulted.

“It’s not all the dermatologists’ fault. Have you tried to get credentialed at a hospital lately? It’s a 1½-inch stack of papers and 8½ hours of electronic medical record training, if you’re lucky. So there are definitely barriers to overcoming this gap,” Dr. Stratman pointed out.

The best solution, he continued, is for dermatologists to take the initiative in educating hospitalists, emergency medicine specialists, and primary care physicians on the common mimickers of cellulitis, especially stasis dermatitis and contact dermatitis. This can happen through grand rounds presentations and feedback to consulting physicians.

“I think dermatologists have to take the lead on this,” Dr. Stratman said.

Underscreening for autoimmune thyroid disease in vitiligo patients

The international Vitiligo Working Group, citing evidence that 19% of patients with vitiligo have concomitant autoimmune thyroid disease and that the risk of developing this endocrine disease doubles every 5 years that a patient has vitiligo, has issued a call to action for dermatologists to ensure that their patients with vitiligo undergo periodic screening (J Am Acad Dermatol. 2017 Jul;77[1]:1-13).

This recommendation was based upon insights provided by a French prospective, observational study of 626 patients with vitiligo. The French investigators found that the risk of autoimmune thyroid disease doubled every 5 years and was associated with female sex, younger age at vitiligo onset, vitiligo on the trunk, and a personal history of autoimmune disease. They recommended screening every 2 years for thyroid-stimulating hormone and free thyroxine levels, as well as checking for serum antithyroperoxidase antibodies (Br J Dermatol. 2013 Apr;168[4]:756-61).

Dr. Stratman noted that some dermatologists may feel that ordering thyroid screening tests is outside their scope of practice. In that case, it’s important to engage with their vitiligo patient’s primary care physician to make sure the screening gets done.

He reported having no financial conflicts of interest regarding his presentation.

SDEF/Global Academy for Medical Education and this news organization are owned by the same parent company.